LS Engine Swap - Confused - Need Suggestions...

[PWagon]

I have been considering upgrading to a LS 5.3 engine for my '86 K5 for a while now. However, I'm confused about a couple of things, and I'm hoping you guys can help me understand.

1.) Injectors- I've read that there's a big difference between car and truck injectors. I prefer the cleaner looking car-intake, and I'll end up putting the car intake on my 5.3 (when I get it). Is there such a big difference between the car and truck injectors? If so, how much difference? Don't the cars and truck engines put out the same horse power?

2.) I want to keep my wiring harness modifications as simple as possible. I've read quite a bit about a "4-wire setup", and it sounds simple. But, I must keep my rig emissions legal (I live in a large city and emission testing is a must). Are you guys familiar with the "4-wire setup" while keeping the engine/harness emissions legal? Would cats be the only "emission" item to keep it legal?

3.) How do I connect my existing air conditioner coolant lines to the new style compressor. The fitters are different and I have no idea how to connect the two. I'd like to run R-12 just because my condenser is still the R-12 model and plus R-12 is darn cold.

4.) Have you guys run across a good webpage or book that helps explain swaps like this? I've searched a lot and have read a lot on websites, but I'm still learning. So, anything you could forward me to would be appreciated.

 

[miniwally]

I have been considering upgrading to a LS 5.3 engine for my '86 K5 for a while now. However, I'm confused about a couple of things, and I'm hoping you guys can help me understand.

1.) Injectors- I've read that there's a big difference between car and truck injectors. I prefer the cleaner looking car-intake, and I'll end up putting the car intake on my 5.3 (when I get it). Is there such a big difference between the car and truck injectors? If so, how much difference? Don't the cars and truck engines put out the same horse power?

If you get a LS6 intake you can use the truck injectors in it but it requires a bit of drilling. Not hard at all, or if you can get car injectors with the right plugs you can go that route.

2.) I want to keep my wiring harness modifications as simple as possible. I've read quite a bit about a "4-wire setup", and it sounds simple. But, I must keep my rig emissions legal (I live in a large city and emission testing is a must). Are you guys familiar with the "4-wire setup" while keeping the engine/harness emissions legal? Would cats be the only "emission" item to keep it legal?

Wiring harness really doesn't have much to do with emissions. There are a few emissions things that can be eliminated but you can have a harness made for your application. 4 wire hookup is the bomb. Call pacific fabrication, they have done this swap a bunch and can help with the tunig, and a good harness

3.) How do I connect my existing air conditioner coolant lines to the new style compressor. The fitters are different and I have no idea how to connect the two. I'd like to run R-12 just because my condenser is still the R-12 model and plus R-12 is darn cold.

Once you bleed the system down to do the switch over you will end up with the new 134? no real way around that, don't know anything about AC stuff.

4.) Have you guys run across a good webpage or book that helps explain swaps like this? I've searched a lot and have read a lot on websites, but I'm still learning. So, anything you could forward me to would be appreciated.

This site and Pacific Fabrication.

 

[sweetk30]

and truck intake makes more tourqe than car i have read. it might look kind of yukky but = more tourqe were we need it with our big trucks.

i am swaping on a trailblazer SS engine cover with a home made bracket to let it bolt to the truck intake. truck - t/b SS cover pic's

and click my 2wd link in my sig to get info and ideas . also www.ls1tech.com for TONS of tech info

also http://www.lt1swap.com/2000harness.htm for standalone harnness mods pin by pin writeup.

 

[Teck]

PM me and you can come see one done. It's not that bad to do.
You don't need cats, you only have to pass a safety inspection because of the age of your K5. It will be cleaner burning with an LS then it is now.
As for the AC there are several factors the you have to address to make it work, mine blows 40*

 

[PWagon]

Awhhhh! I think I'm gonna be sick. I bought a 5.3 from a guy in Ft Worth, and the deal seemed legit. The guy was a real motor-head and had a shop full of hotrods. We talked a good while and he had me convinced it was a good engine. Well... I just got it home, compression tested it, and it's worn smooth out (65 psi per cylinder on average). I think I'm gonna be sick. I otta whip his ass! Anyone want to buy a "good-used" 5.3???

 

[PWagon]

Anyone of you guys rebuilt a 5.3 LS before? I'm wondering if I should just go pick up a low mileage LS from a salvage yard. But with my luck the damn thing would be worn out too. Any suggestions?

 

[metalneverdies]

Awhhhh! I think I'm gonna be sick. I bought a 5.3 from a guy in Ft Worth, and the deal seemed legit. The guy was a real motor-head and had a shop full of hotrods. We talked a good while and he had me convinced it was a good engine. Well... I just got it home, compression tested it, and it's worn smooth out (65 psi per cylinder on average). I think I'm gonna be sick. I otta whip his ass! Anyone want to buy a "good-used" 5.3???

Try a drop or two of oil in each cyl before you rip it apart. Maybe do a leak dow. Test to check where your air is leaking out of.

 

[496truck]

Exactly. How long has it been sitting? Are you cranking it with a starter while on a stand? A little bit of light oil on the cyl walls will improve those numbers, and real world situation the rings will have oil on them. Dry cylinders from an engine sitting in storage for a while will always result in lower compression test numbers.

 

[Chevy305]

Make sure the throttle blade is pinned open when you do your test.